Most sharks are small
What draws many divers is of course the drama and fascination of the larger sharks and on the top list there are usually; hammerhead shark, whale shark, white shark, tiger shark, brugd, bull shark, galapagos shark, thresher shark, yearfin shark, ctiron shark, nurse shark and sand tiger shark but of course there are many many more. There are roughly 500 different known shark species today, of which roughly 200 are completely bottom-dwelling. Just over 200 live both on the bottom and in the open sea. Only about 25 different species live in the open sea alone. Close to 300 of the shark species are no larger than 1 meter, just over 50 species are between 1 and 1,5 meters, 50 of the species are 1,5–3 meters and 25 species are over 3 meters.
So it's not often the big animals we're talking about, but of course they're the most impressive and attract the most divers. Nevertheless, it's very fascinating to see small catsharks and epaulettes.
tea sharks of 40-70 cm in tropical seas. Often on night dives you can see them walking around on the bottom and in fact several are known as “walking sharks”
All sharks are cartilaginous fish and lack a swim bladder. Cartilage is lighter than bone and with the help of the well-developed fins they can easily glide through the oceans without wasting energy. Many sharks have to keep swimming all the time to oxygenate themselves and when they stop they slowly sink to the bottom. However, many sharks can lie still on the bottom for a long time and pump fresh oxygen-rich water themselves through their gills and do not have to swim at all all the time.
Do sharks lay eggs?
Some sharks lay eggs but they are few in number. Almost all sharks have internal fertilization and give birth to "live" young. That is, they hatch when they are released. Sharks have more senses than humans. They also have a sixth sense that is sometimes called the electrical sense. All living animals send out small electrical impulses. These impulses are sensed by the shark through small pores called ampullae of Lorenzini. They are filled with "jelly" and sit all over the body but mainly in the nose. Through these pores, the shark can sense fish and other animals even though they are out of sight. It helps the sharks when they hunt. It is believed that this electric sense also helps them navigate.
Many shark species are threatened, mainly due to overfishing. In the world's oceans, approximately 120 million sharks are killed annually, while the population has decreased by over 90% since 20 years ago. The public's interest has mostly been directed towards the "dangerousness" of man-eating sharks. The knowledge that there are also sharks that are harmless to humans and also useful has been poor. Now, however, the interest is growing as people are aware that there are endangered species among the sharks. Sharks are high up in the food chain and have a key role in the ecosystem. We as divers therefore have an important role to go and see live sharks in nature and their natural environment. Because a live shark has far more value than one on a plate.
Experience sharks
Welcome to book your shark adventure with us at Scuba Travel. These are truly fascinating, exciting, awe-inspiring animals but in most cases don't even care about us divers. On the contrary, unfortunately they often swim away too quickly and it is therefore important to know where to go to see these incredible animals and learn to interact with them so that you really get to experience them up close.
If you want to read more about the other animals on our BIG 5 list, you can continue here: Turtles, manta ray, whale shark, Dolphins
